1. Field of the Invention
The present invention relates to a lens device, and specifically relates to a lens device capable of holding a lens so as to be movable in a direction perpendicular to the optical axis.
2. Description of the Related Art
Heretofore, there have been various types of proposed optical devices provided with a vibration isolating device to correct the image forming position by moving a stated vibration proof lens included in said optical system in a direction perpendicular to the optical axis in accordance with vibration so as to prevent image deterioration generated by vibration of the optical device via unsteady hands or the like.
Normally, in vibration isolating devices constructed so as to move the aforesaid stated vibration proof lens in a direction perpendicular to the optical axis, a movable frame must be driven in a first direction perpendicular to the optical axis relative to a stationary frame, and a lens holding frame which holds said vibration proof lens must be driven in a second direction perpendicular to the optical axis relative to said movable frame. When such a construction is used, the vibration proof lens can be moved independently in said first direction perpendicular to the optical axis and said second direction perpendicular to the optical axis.
Proposed construction of vibration proof lenses include a construction wherein three frames comprising a stationary frame, movable frame, and vibration proof lens holding frame are arranged in the direction of a plane intersecting the optical axis, i.e., a construction wherein a movable frame is arranged within a stationary frame and a lens holding frame is arranged within said movable frame as disclosed in Japanese Laid-Open Patent Application No. 3- 186823. Another proposed construction includes three frames stacked in the direction of the optical axis as disclosed in Japanese Laid-Open Patent Application No. 4-18515.
The former construction disclosed in Japanese Laid-Open Patent Application No. 3-186823, however, is disadvantageous insofar as the diameter of the vibration isolating lens device, i.e., the dimension of the vibration proof lens in a direction intersecting the optical axis of the vibration proof lens, is increased due to the arrangement of the three frames in the direction of a plane perpendicular to the optical axis.
The latter construction disclosed in Japanese Laid-Open Patent Application No. 4-18515, on the other hand, is disadvantageous insofar as the dimension of the vibration isolating lens device is increased in the optical axis direction although the dimension is reduced in the diameter direction of the vibration proof lens due to the stacking of the frames in the direction of the optical axis.